In two-stage combustors, the combustor is comprised of two sub-chambers, one for the pilot stage of the burner, and the other for the main stage of the burner. The pilot stage operates the engine at low power settings, and is kept running at all conditions. The pilot stage is also used for operability of the engine to prevent flame extinction. The main stage is additionally operated at medium- and high-power settings. The arrangement of two-stage combustors involves typically complex paths, and may make avoiding dynamic ranges with their increased-complexity geometry more difficult. Also, problems may occur in trying to achieve a proper temperature profile. Finally, durability has been problematic.